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Abstract:

A security element for a security paper, value document or the like,
having a carrier which has a reflective areal region which is divided
into a multiplicity of reflective pixels. The area of each pixel is
smaller than the area of the reflective areal region by at least one
order of magnitude. Each pixel has at least one reflective facet which is
formed in a surface of the carrier, and the at least one reflective facet
reflects light incident along a predetermined direction on the areal
region directionally in a reflection direction predefined by the
orientation of the facet. The orientations of the facets of different
pixels have a substantially random variation over the reflective areal
region.

Claims:

1.-22. (canceled)

23. A security element for a security paper, comprising a carrier having
a reflective areal region which is divided into a multiplicity of
reflective pixels, the area of each pixel being smaller than the area of
the reflective areal region by at least one order of magnitude, each
pixel comprising at least one reflective facet which is formed in a
surface of the carrier, the at least one reflective facet reflecting
light incident along a predetermined direction on the areal region
directionally in a reflection direction predefined by the orientation of
said facet, and the orientations of the facets of different pixels having
a substantially random variation over the reflective areal region.

24. The security element according to claim 23, wherein the orientations
of the facets of different pixels have a substantially random variation
around different average orientations predefined in a region-based
manner.

25. The security element according to claim 23, wherein several of the
pixels respectively have several reflective facets of identical
orientation which form a periodic or aperiodic sawtooth grating.

26. The security element according to claim 23, wherein the facets are
configured as substantially planar area elements.

27. The security element according to claim 23, wherein the orientations
of the facets of different pixels have a substantially random variation
only in a parameter determining the orientation of the facets.

28. The security element according to claim 23, wherein the variation of
the reflection directions that is predefined by the substantially random
variation of the orientations of the facets of different pixels amounts
to at least about 1.degree..

29. The security element according to claim 23, wherein when there are
provided several facets per pixel which form a periodic or aperiodic
sawtooth grating, the width of the sawteeth is between about 1 μm and
about 300 μm.

30. The security element according to claim 23, wherein the pixels are
arranged on a regular grid.

31. The security element according to claim 23, wherein there is formed
on the facets at least in certain regions a reflection-enhancing coating.

32. The security element according to claim 23, wherein there is formed
on the facets at least in certain regions a color-shifting layer.

33. The security element according to claim 23, wherein the maximum
extension of a pixel is between 5 μm and 5 mm.

34. The security element according to claim 23, wherein the reflective
areal region is divided into at least two portions which have different
average reflection directions of the pixels that are predefined by
different average orientations.

35. The security element according to claim 34, wherein the at least two
portions with different average reflection directions are distributed
over different, mutually interlaced partial areas.

36. The security element according to claim 23, wherein the orientation
of the facets is such that the reflective areal region has a continuous
course of the average reflection directions of the pixels.

37. The security element according to claim 23, wherein the security
element is combined with a micro-optic representation arrangement into a
total representation.

39. The value document according to claim 38, comprising a security
feature which is based on magnetically aligned pigments of optically
variable security inks and which has an optical appearance substantially
comparable with the appearance of the security element.

40. The value document according to claim 38, wherein there is formed on
the facets of the security element at least in certain regions a
color-shifting layer, wherein the color-shifting effect of the
color-shifting layer is such that the color-shift effects of the security
element and the color-shift effects of the security feature based on
magnetically aligned pigments correspond to each other.

41. The value document according to claim 38, wherein the security
element and the security feature based on magnetically aligned pigments
respectively have a further optical effect, and wherein the further
optical effects produced correspond to each other.

42. A method of making a security element for security papers, comprising
the steps: providing a carrier having a surface that is so
height-modulated in an areal region that the areal region is divided into
a multiplicity of pixels with respectively at least one facet; coating
said facets so as to form reflective facets which reflect light incident
along a predetermined direction on the areal region per pixel
respectively directionally in a reflection direction predefined by their
orientation; making the area of each pixel smaller than the area of the
areal region by at least one order of magnitude; and arranging the
orientations of the facets of different pixels to have a substantially
random variation over the reflective areal region.

43. An embossing tool comprising an embossing area capable of embossing
the form of the facets of the security element recited in claim 23 into
the carrier.

44. Use of a security element according to claim 23 as a master for
exposing a volume hologram.

Description:

[0001] The present invention relates to a security element for a security
paper, value document or the like, to a value document having such a
security element, and to a method for manufacturing such a security
element.

[0002] Objects to be protected are frequently equipped with a security
element which permits verification of the authenticity of the object and
at the same time serves as protection from unauthorized reproduction.

[0004] For such a security element it is known to employ optically
variable security inks as are described e.g. in EP 0 227 423 A2. Such
security inks contain platelet-shaped pigments with a thin-film
interference coating, so that for a viewer the color of the individual
pigments depends on the viewing angle. The security inks with the
described platelet-shaped pigments can be printed on a bank note such
that the pigments are aligned approximately parallel to the surface of
the bank note, and the printed area changes its color in accordance with
the thin-film coating of the pigments upon tilting of the bank note.

[0005] It is further known to provide such pigments with an additional
magnetic layer (U.S. Pat. No. 4,838,648), so that the pigments can then
be aligned by means of suitable magnets and fixed (U.S. Pat. No.
7,517,578 B2). This makes it possible for the pigments to be aligned
parallel to each other substantially more precisely, on the one hand,
which leads to a considerably higher chroma (=more brilliant colors). On
the other hand, it provides the possibility of orienting the pigments not
only parallel to the substrate surface, but in principle in any
direction. In particular, the pigments of different regions of the
security element can also be aligned in different directions. Depending
on the magnet assembly used, there can be achieved between the
differently oriented regions relatively abrupt as well as gentle
transitions.

[0006] From JP 2008-80609 A there is known a further method for aligning
the platelet-shaped pigments wherein the security ink with the pigments
is so applied to an embossed relief structure that the pigments are
aligned approximately parallel to the relief. By suitable design of the
relief there can be realized regions with differently oriented pigments
and accordingly different colors.

[0007] The described optically variable security inks are relatively
expensive, on the one hand. On the other hand, the alignment of the
pigments via magnets is of course limited, because the magnetic fields
necessary for alignment cannot be arbitrarily formed. Further, the
security elements cannot be especially finely resolved, which is due to
the usually employed screen printing processes, on the one hand, and to
the transitions of the necessary magnetic fields not being arbitrarily
sharp, on the other hand.

[0008] Besides the color change, the security inks also frequently lead to
a glitter effect similar to metallic lacquering on automobiles.

[0009] On these premises, the invention is based on the object of avoiding
the disadvantages of the prior art and in particular providing a security
element with which at least one of the described effects (such as e.g.
the glitter effect) of the security inks can be obtained without
employing security inks.

[0010] According to the invention this object is achieved by a security
element for a security paper, value document or the like, having a
carrier which has a reflective areal region which is divided into a
multiplicity of reflective pixels, whereby the area of each pixel is
smaller than the area of the reflective areal region by at least one
order of magnitude, whereby each pixel has at least one reflective facet
which is formed in a surface of the carrier, whereby the at least one
reflective facet reflects light incident along a predetermined direction
on the areal region directionally in a reflection direction predefined by
the orientation of said facet, whereby the orientations of the facets of
different pixels have a substantially random variation over the
reflective areal region.

[0011] "Pixels" are understood here to be small partial regions of the
reflective areal region, which can not only have an arbitrary outline
form, but in particular need also not be arranged on a regular grid.

[0012] The chosen formulation according to which the orientations of the
facets of different pixels have a substantially random variation over the
reflective areal region takes account of the fact that a random variation
can also be realized for example with the help of computer-generated
"random numbers" which, strictly speaking, are deterministic.

[0013] The substantially random variation of the orientations of the
facets is preferably so realized that there is first associated with the
pixels e.g. in a region-based manner a certain preferential orientation,
starting out from which the orientation of the facets of the individual
pixels is then varied for example on the basis of computer-generated
random numbers or pseudo-random numbers. It can thus be achieved in
particular that the orientations of the facets of individual pixels
fluctuate around an average orientation in a region-based manner. The
random fluctuation of the orientation can, in special implementation
variants, be present only within predefined limits and/or according to a
predefined distribution, for example normally or uniformly distributed.

[0014] With such a security element it is possible to precisely adjust for
each pixel the orientation and thus also the direction in which incident
light is reflected, so that a glitter effect can be realized in simple
fashion. In the security element of the invention, the reflective area,
which can be e.g. a planar or a curved area, can thus still be perceived
as a planar or curved area but at the same time shows the desired glitter
effect.

[0015] The substantially random variation of the orientations of the
facets over the reflective areal region is understood here to mean in
particular that the reflection directions are different for the majority
of the pairs of directly neighboring pixels or also for all pairs of
directly neighboring pixels. Preferably, the areal region is at the same
time perceptible to a viewer in its actual spatial form.

[0016] The security element of the invention can have in particular an
optical appearance that practically matches that of magnetically aligned
pigments of optically variable security inks. For this purpose, there is
chosen a pixel size that corresponds approximately to the size of the
pigments employed in such inks, for example 30 μm, and the average
orientation of the facets of different pixels is chosen analogously to
the average orientation of the pigments. The glitter effect of such inks
is based on the individual pigments not reflecting exactly in a
predefined direction, but a certain random variation of the reflection
directions being present. The orientations of the facets of different
pixels in the security element of the invention likewise have such a
variation, which results in a comparable glitter effect.

[0017] The area of the areal region and the area of the pixels are
understood here to be in particular respectively the area upon projection
in the direction of the macroscopic surface normal of the areal region
onto a plane. Preferably, the area of each pixel is smaller than the area
of the reflective areal region by at least two orders of magnitude.

[0018] In the security element of the invention, the orientations of the
facets of different pixels advantageously have a substantially random
variation around different average orientations predefined in a
region-based manner.

[0019] Several of the pixels preferably respectively have several
reflective facets of identical orientation which form a periodic or
aperiodic sawtooth grating. It is also possible for all pixels to
respectively have several, preferably the same number of, reflective
facets of identical orientation.

[0020] The facets are preferably configured as substantially planar area
elements, which facilitates the manufacture. The chosen formulation
according to which the facets are configured as substantially planar area
elements takes account of the fact that, for manufacturing reasons,
perfectly planar area elements can normally never be manufactured in
practice. The facets can alternatively also be configured as curved (e.g.
concave, convex or wavy) area elements. The curvature of the area
elements is expediently low here.

[0021] Orientation is understood here to be in particular the inclination
of the reflective facets and/or the azimuth angle of the reflective
facets. The orientation of the facets can of course also be determined by
other parameters. In particular, the parameters in question are two
mutually orthogonal parameters, such as e.g. the two components of the
normal vector of the respective facet.

[0022] The random variation of the orientations can be effected here in
one or two dimensions or spatial directions. The security element of the
invention can be configured in particular such that the orientations of
the facets of different pixels have a substantially random variation only
in one of the parameters determining the orientation of the facets. Thus,
the random variation can in particular also relate only to the slope or
only to the azimuth angle, or the variation of the orientations of the
facets can be chosen such that a reflected light beam incident in a
corresponding partial region "fans out" around a predefined rotation
direction.

[0023] Preferably, the variation of the reflection directions that is
predefined by the variation of the orientations of the facets of
different pixels amounts to at least about 1°, preferably at least
about 3°, particularly preferably at least about 10°.

[0024] In the security element of the invention, the reflective facets can
have a reflection-enhancing, in particular a reflective, coating.
Reflection-enhancing coatings for the purposes of the invention are also
coatings that increase the reflectance for example only by about 20% to
about 50%, such as e.g. semi-transparent layers, whereas reflective
coatings involve a very high reflectance. The reflection-enhancing
coating can be a metallic coating, which is vapor-deposited for example.
As a coating material there can be employed in particular aluminum, gold,
silver, copper, palladium, chromium, nickel and/or tungsten as well as
alloys thereof. Alternatively, the reflection-enhancing coating can be
formed by a coating with a material with a high refractive index.

[0025] In particular there can be formed on the facets at least in certain
regions a color-shifting layer. This makes it possible to adjust the
desired color-shifting effect to pixel size and thus in a highly resolved
manner. According to an advantageous embodiment, color-shifting layers
differing in certain regions can also be formed on the facets.

[0026] The reflection-enhancing coating as well as the color-shifting
layer can be present in the form of patterns, characters or encodings
and/or have gaps in the form of patterns, characters or encodings.

[0027] The maximum extension of a pixel is preferably between about 5
μm and 5 mm, preferably between 10 μm and 300 μm, particularly
preferably between 20 μm and 100 μm.

[0028] The width of the sawteeth or, in the case of periodic sawtooth
gratings, the grating period per pixel is preferably between 1 μm and
300 μm, preferably between 3 μm and 100 μm, particularly
preferably between 5 μm and 30 μm. The width of the sawteeth or the
grating period is chosen in particular such that at least two facets of
identical orientation are contained per pixel and that diffraction
effects practically no longer play a part for incident light (e.g. from
the wavelength range of 380 nm to 750 nm). Because no, or no practically
relevant, diffraction effects occur, the facets can be designated
achromatic facets, or the pixels achromatic pixels, which cause a
directionally achromatic reflection. The security element thus has an
achromatic reflectivity with regard to the grating structure present
through the facets of the pixels, whereby with increasing grating period
the security element shows an increasingly more brilliant appearance,
i.e. a more pronounced glitter effect. A possibly still present
visibility of a diffraction image arising from the sawtooth grating can
be minimized--should this be desired--in particular by a variation of the
grating period.

[0029] The color-shifting layer can be configured in particular as a
thin-film system or thin-film interference coating. There can be realized
here e.g. a layer sequence of metal layer--dielectric layer--metal layer
or a layer sequence of at least three dielectric layers, whereby the
refractive index of the middle layer is lower than the refractive index
of the two other layers. As a dielectric material there can be employed
e.g. ZnS, SiO2, TiO2, MgF2.

[0030] The color-shifting layer can also be configured as an interference
filter, thin semi-transparent metal layer with selective transmission
through plasma resonance effects, nanoparticles, etc. The color-shifting
layer can in particular also be realized as a liquid-crystal layer,
diffractive relief structure or subwavelength grating. A thin-film system
constructed of reflector, dielectric, absorber (formed on the facets in
this order or, upon viewing of the security element through the carrier,
in the reverse order) is also possible. If the security element is to be
viewable from both sides, the layer sequence of
absorber/dielectric/reflector/dielectric/absorber is expedient.

[0031] In the security element of the invention, at least two facets can
preferably be provided per pixel. There can also be three, four, five or
more facets.

[0032] The security element can be configured in particular such that the
azimuth angles of the facets of the individual pixels are randomly
distributed values between 0° and 360° (but each facet has
the same azimuth angle per pixel). Also, it is possible that the slopes
of the facets per pixel are randomly distributed according to a normal
distribution (here, too, each facet has the same slope per pixel).

[0033] The reflective areal region of the security element can be divided
into at least two partial regions or portions in which the pixels have
different average orientations, or different average reflection
directions predefined by the different average orientations. Thus, all
facets can e.g. have the same azimuth angle. In the first of the two
partial regions, the inclinations of the facets are then chosen for
example randomly between 10° and 20°, while the
inclinations of the facets in the second partial region of the two
partial regions are chosen between -20° and -10°. Upon
tilting of the security element, the first partial region then appears
bright in one case and the second partial region in the other case
depending on the illumination, i.e. the representation flips from a
positive to a negative representation.

[0034] Alternatively, it is e.g. also possible that the azimuth angles are
uniformly distributed over all possible angles, and the inclinations are
different in the two partial regions but respectively fixed, for example
10° in the first partial region and 30° in the second
partial region. Such a representation has the special property that
although it flips from a positive to a negative representation upon
tilting of the security element, such a flip effect is surprisingly
lacking upon rotation of the security element within its plane.

[0035] When the facets have a color-shifting layer, the colors of the
different partial regions can be different, because the color-shifting
coating is looked at from different angles.

[0036] According to a preferred embodiment, the two partial regions can
also be distributed over different, mutually interlaced partial areas. In
this way there can be produced for example a so-called tilt image.

[0037] Further, with the security element of the invention there can be
produced the impression that a "noisy" area is present (preferably in a
reflective area). Additionally, the facets of the pixels can be oriented
such that there occurs from certain viewing angles a simultaneous bright
lighting up of many pixels. For this purpose, the reflective areal region
on the carrier is divided into at least two partial regions, so that the
pixels in the first partial region have a random orientation, while the
pixels of the second or the further partial regions all have the same or
at least almost the same orientation respectively per partial region. The
light from a light source is then scattered in all directions from many
angles in the first partial region, while the light is respectively
reflected in a narrow angular range in the further partial regions. A
viewer then sees only a noisy representation with randomly lighting up
pixels (glitter effect) from most angles, while the further partial
regions light up very brightly from certain angles.

[0038] With the security element of the invention there is fundamentally
provided the possibility of simulating practically all optical effects
attainable with magnetically oriented pigments. Thus, there are to be
mentioned in particular the "rolling bar" or "double rolling bar" effects
stated in U.S. Pat. No. 7,517,578 B2. Expediently, the orientation of the
facets is chosen here such that the reflective areal region has a
continuous course of the average reflection directions of the pixels. By
a suitable combination of the security element of the invention with
magnetic materials, for example incorporation of magnetic layers or
combination with magnetic inks, there can of course also be provided
magnetic properties which can in particular be machine-readable.

[0039] Preferably, the attainable optical effects are continued
periodically on the security element. Thus, a multiplicity of such
effects can be repeated periodically e.g. for a security element
configured as a security thread, so that the corresponding effect can be
perceived in multiple fashion upon arrangement in a window.

[0040] The pixels preferably have a rectangular or square outline form.
However, they can also have special other outline forms which become
visible under the microscope for example. In particular, the pixels can
also have different outline forms. Thus, a portion of the pixels can e.g.
have outlines in the form of a symbol or a number.

[0041] Preferably, the pixels are arranged in a regular grid.

[0042] In at least one portion of the pixels there can additionally be
written a motif, e.g. a microtext, a logo or an encoding. The motif can
be written here either into the facets, or a small portion of the pixels
has no facets but is filled with the motif, e.g. a microtext.

[0043] The security element of the invention can be combined with other
known security features. For example, an interlaced combination with a
hologram, in particular a true-color hologram or a Kinegram, is possible.

[0044] According to a preferred embodiment, the security element of the
invention can be combined with a micro-optic representation arrangement
into a total representation. For example, the security element of the
invention can be combined with a micro-optic representation arrangement
with microstructures as well as micro-imaging elements for enlarged
imaging of the microstructures, e.g. microlens or concave micromirror
arrays, or microlens or concave micromirror images.

[0045] The facets of the pixels can be configured as a periodic or
aperiodic sawtooth structure. In particular, it is possible that the
facets are formed by embossing the surface.

[0046] The reflective areal region of the security element can have in
particular the form of a motif (e.g. letter, number, symbol, etc.).

[0047] The security element of the invention can further be equipped with
one or several functional layers for use as a security element for
security papers, value documents and the like, in particular with a
heat-seal finish, with protective layers, e.g. a transparent protective
lacquer, cover layers, adhesive layers or layers with visually and/or
machine-detectable security features.

[0048] There is further provided a value document having the security
element of the invention, whereby the security element can be configured
according to the developments of the invention.

[0049] Besides the simulation of the optical effects attainable with
magnetically oriented pigments, such effects can also be combined with
the security element of the invention in targeted fashion. Thus,
according to an advantageous embodiment, the value document can also
have, besides the security element of the invention, a security feature
that is based on magnetically aligned, preferably platelet-shaped
pigments of optically variable security inks and that has an optical
appearance substantially comparable to the appearance of the security
element. Such security features can be taken in particular from U.S. Pat.
No. 7,517,578 B2, whose disclosure on the manufacture and properties of
such security features is incorporated into the present description. The
magnetic pigments are normally present here in the form of a motif which
contains a region in which the magnetic pigments are aligned relatively
to the surface of the ink layer.

[0050] Such a substantially comparable optical appearance can consist in
particular in there being formed on the facets of the security element at
least in certain regions a color-shifting layer, and the color-shifting
effect of the color-shifting layer being adjusted such that the
color-shift effects of the security element and of the security feature
based on magnetically aligned pigments correspond to each other, i.e.
have the same color depending on the tilting angle.

[0051] Alternatively or additionally, the security element of the
invention and the security feature based on magnetically aligned pigments
can respectively have a further optical effect, whereby the produced
further optical effects correspond to each other.

[0052] Preferably, the further optical effect is formed by a kinetic
effect. In particular there are to be mentioned here the "rolling bar" or
"double rolling bar" effects stated in U.S. Pat. No. 7,517,578 B2.
Expediently, the kinetic effects of the security element and of the
security feature based on magnetically aligned pigments come about upon
tilting of the value document in the parallel direction, in the opposite
direction) (180° or in the perpendicular direction to each other.

[0053] Other kinetic effects upon tilting of the value document can also
be realized, such as e.g. so-called flip, running or pumping effects. The
motion is advantageously effected here in the same direction or in the
opposite direction. If upon tilting of the value document the security
element of the invention and the security feature based on magnetically
aligned pigments show for example a pumping effect (concentric motion
around a fixed point), either both hence show an extension or both a
contraction (same-direction motion) or alternatively the security element
shows an extension effect while the security feature based on
magnetically aligned pigments contracts (opposite-direction motion).
Accordingly, in the case of so-called flip effects, the security element
and the security feature based on magnetically aligned pigments flip from
a positive to a negative representation upon tilting (same-direction
motion), or only the security element flips in this way while the
security feature based on magnetically aligned pigments flips from a
negative to a positive representation (opposite-direction motion).

[0054] Besides kinetic effects, the security element of the invention and
the security feature based on magnetically aligned pigments can also show
a corresponding three-dimensional effect, as can be taken for example
from U.S. Pat. No. 7,517,578 B2.

[0055] The security element of the invention and the security feature
based on magnetically aligned pigments can be arranged either on the same
side of the value document or on opposing sides of the value document. An
arrangement on opposing sides of the value document has here the
advantage that any minimal color deviations between the security element
of the invention and the security feature based on magnetically aligned
pigments that might be present are not, or hardly, perceived.

[0056] According to a development of the invention, the reflective areal
region of the security element as well as the security feature based on
magnetically aligned pigments can have the form of a matching motif (e.g.
letter, number, symbol, etc.). Preferably, the motifs are formed on the
value document in different sizes. For example, the dimensions of the
motif of the security feature based on magnetically aligned pigments
amounts to about 15 mm and the dimensions of the motif of the security
element of the invention configured e.g. as a security thread amounts to
about 4 mm.

[0057] The invention also comprises a method for manufacturing a security
element for security papers, value documents or the like, wherein the
surface of a carrier is so height-modulated in an areal region that the
areal region is divided into a multiplicity of pixels with respectively
at least one facet, and the facets are provided with a coating so as to
form reflective facets which reflect light incident along a predetermined
direction on the areal region per pixel respectively directionally in a
reflection direction predefined by their orientation, whereby the area of
each pixel is chosen to be smaller than the area of the areal region by
at least one order of magnitude, and whereby the orientation of the
facets of different pixels have a substantially random variation over the
reflective areal region.

[0058] The manufacturing method of the invention can be developed in
particular such that the security element of the invention as well as the
developments of the security element of the invention can be
manufactured.

[0059] For producing the height-modulated surface of the carrier there can
be employed known microstructuring methods, such as e.g. embossing
methods. Thus for example also using methods known from semiconductor
fabrication (photolithography, electron beam lithography, laser-beam
lithography, etc.) suitable structures in resist materials can be
exposed, possibly refined, molded and employed for fabricating embossing
tools. There can be used known methods for embossing in thermoplastic
foils or into foils coated with radiation-curing lacquers. The carrier
can have several layers which are successively applied and optionally
structured and/or can be assembled from several parts.

[0060] The security element of the invention can be manufactured in
particular such that a further, embossed security feature is produced in
the same working step. This may be in particular an optically variable
security feature, such as e.g. a hologram, a non-noisy sawtooth structure
(tilt images, kinematic effects, 3D representations, etc.), microlens or
concave micromirror arrays, or microlens or concave micromirror images.

[0061] Further, the at least one further security feature can according to
the invention be metallized or provided with a metallic coating in the
same working step as the facets.

[0062] The security element can be configured in particular as a security
thread, tear thread, security band, security strip, patch or as a label
for application to a security paper, value document or the like. In
particular, the security element can span transparent regions or
recesses.

[0063] The term security paper is understood here to be in particular the
not yet circulable precursor to a value document, which can have besides
the security element of the invention for example also further
authentication features (such as e.g. luminescent substances provided
within the volume). Value documents are understood here to be, on the one
hand, documents produced from security papers. On the other hand, value
documents can also be other documents and objects that can be provided
with the security element of the invention in order for the value
documents to have uncopiable authentication features, thereby making it
possible to check authenticity and at the same time preventing unwanted
copying.

[0064] There is further provided an embossing tool having an embossing
area with which the form of the facets of a security element according to
the invention (including its developments) can be embossed into the
carrier or into the surface of the carrier.

[0065] The embossing area preferably has the inverted form of the surface
contour to be embossed, whereby this inverted form is preferably produced
by the formation of corresponding depressions.

[0066] Further, the security element of the invention can be used as a
master for exposing volume holograms or for purely decorative purposes.

[0067] To expose the volume hologram, a photosensitive layer in which the
volume hologram is to be formed can be brought, directly or through the
intermediary of a transparent optical medium, in contact with the front
side of the master and thus with the front side of the security element.

[0068] Then the photosensitive layer and the master are exposed with a
coherent light beam, thereby causing the volume hologram to be written
into the photosensitive layer. The procedure can be identical or similar
to the procedure for producing a volume hologram as described in DE 10
2006 016 139 A1. The basic procedure is described for example in
paragraphs nos. 70 to 79 on pages 7 and 8 of the stated print in
connection with FIGS. 1a, 1b, 2a and 2b. The total content of DE 10 2006
016 139 A1 with regard to the manufacture of volume holograms is hereby
incorporated into the present application.

[0069] It is evident that the features mentioned hereinabove and those to
be explained hereinafter are usable not only in the stated combinations,
but also in other combinations or in isolation, without going beyond the
scope of the present invention.

[0070] Hereinafter the invention will be explained more closely by way of
example with reference to the attached figures, which also disclose
features essential to the invention. For more clarity, the figures do
without a representation that is true to scale and to proportion. There
are shown:

[0071]FIG. 1 a plan view of a bank note having a security element 1
according to the invention;

[0072]FIG. 2 an enlarged plan view of a part of the first areal region 3
of the security element 1;

[0076]FIG. 6 a cross-sectional view for explaining the formation of a
color-shift thin-film system on the facets;

[0077] FIG. 7 a further sectional view for explaining a further
color-shift thin-film system on the facets;

[0078] FIGS. 8a-8c views of a security element according to the invention
according to a further embodiment in different tilted positions;

[0079] FIGS. 9a-9c views of a security element according to the invention
according to yet a further embodiment in different tilted positions, and

[0080]FIG. 10 a plan view of a further embodiment of the security element
of the invention;

[0081]FIG. 11 a schematic sectional view of the security element of FIG.
10;

[0082]FIG. 12 a schematic view for explaining the mode of function of the
micro-optic representation arrangement in the second areal region of the
security element of the invention;

[0083]FIG. 13 a schematic sectional view of a further embodiment of the
security element of the invention;

[0084] FIG. 14 a sectional view of a further embodiment of the security
element of the invention;

[0085]FIG. 15 a sectional view of a further embodiment of the security
element of the invention, and

[0086]FIG. 16 a schematic sectional view of an embossing tool for
manufacturing the security element of the invention according to FIG. 11.

[0087] In the embodiment shown in FIG. 1, the security element 1 of the
invention is integrated in a bank note 2 such that the security element 1
is visible from the front side of the bank note shown in FIG. 1.

[0088] The security element 1, which is configured as a reflective
security element with a rectangular outside contour, comprises a first
areal region 3 (here the digits of the number 50) as well as a second
areal region 4 adjoining the first areal region 3, whereby the two areal
regions 3 and 4 together fill the total area that is limited by the
rectangular outside contour.

[0089] The first areal region 3 is divided into a multiplicity of
reflective pixels 5 of which a small portion are represented enlarged in
FIG. 2 as a plan view. The pixels 5 are square here and have an edge
length in the range of 10 to several 100 μm. Preferably, the edge
length is no greater than 300 μm. In particular, it can be in the
range between 20 to 100 μm.

[0090] The edge length of the pixels 5 is so chosen that the area of each
pixel 5 is smaller than the area of the first areal region 3 (digits of
the number 50) by at least two orders of magnitude.

[0091] Each pixel 5 has several reflective facets 6 of identical
orientation in the embodiment described here. The facets 6 are the
inclined areas of a reflective sawtooth grating. In a modification not
represented, however, it is also possible that several or all pixels 5
respectively have only a single facet 6.

[0092] In FIG. 3 there is represented the sectional view along the line 7
for three neighboring pixels 51, 52 and 53, whereby the
representation in FIG. 3, as also in the other figures, is not true to
scale but in part strongly exaggerated for the sake of better
representability. Further, for simplifying the representation in FIG. 3,
as also in FIGS. 4 and 5, the reflective coating on the facets 6 is not
drawn in.

[0093] The sawtooth grating of the pixels 51, 52 and 53 is
formed in an upper side 8 of a carrier 9, whereby the thus structured
upper side is preferably coated with a reflective coating. The carrier 9
may be e.g. a radiation-curing plastic (UV resin) which is applied to a
carrier foil not shown (for example a PET foil).

[0094] As to be seen in FIG. 3, the inclination a of the facets 6 is
identical in each individual pixel 51, 52 and 53. However,
the inclination of facets 6 of neighboring pixels 51, 52,
53 is different. Furthermore, the grating period d3 of the
sawtooth structure of the pixel 53 is also different from the
grating periods d1 and d2 of the sawtooth structures of the
pixels 51 and 52. Due to the different orientation of the
facets 6 of the individual pixels 51, 52 and 53, light
L1, L2, L3 incident along a predetermined direction R is
reflected by each pixel 51, 52, 53 directionally in
different reflection directions, as represented schematically in FIG. 3.
Because the facets 6 of the pixels 5 of the first areal region 3 are
always oriented differently, there is obtained for the viewer a
glittering effect or an effect comparable with a metallic lacquering.

[0095] The different orientation of the facets 6 can be adjusted not only
by the choice of the angle of inclination α of the facets 6, but
also by different azimuth angles Φ. Relative to the direction
according to the arrow P1 in FIG. 2, the azimuth angle Φ1 of the
facets 6 of the pixels 51, 52 and 53 respectively amounts
to 90°.

[0096] The azimuth angle Φ2 of the facets 6 of the pixel 54
amounts to approx. 120° (relative to the direction of the arrow
P2), however, and the azimuth angle (D3 of the facets of the pixel
55 amounts to approx. 280° (relative to the direction of the
arrow P3). The sectional views along the lines 10, 11 of the pixels
54 and 55 are represented in FIGS. 4 and 5.

[0097] Through the thus existing different orientation of the individual
facets 6 in the pixels 5, the above-described glitter effect is achieved
upon viewing of the first areal region 3.

[0098] The second areal region 4 can be configured as a normally
reflective planar area, so that the digits of the number 50 (first areal
region 3) stand out clearly from the second areal region 4 on account of
the described effect.

[0099] The azimuth angles can for example be chosen randomly for the
individual pixels 5. In particular, random values between 0 and
360° can be selected. For the slope a of the facets 6 there can be
chosen for example values from the range of 10° to 20° and
from the range of -20° to -10°. It is also possible to
choose the slope of the facets from a range of for example -20° to
20°. Here, too, the slopes can again be chosen randomly.

[0100] It is possible that the randomly chosen slope α corresponds
to a normal distribution. The randomly chosen azimuth angles Φ can in
particular be uniformly distributed. The grating period or width of the
sawteeth d is preferably above 1 μm and in particular above 3 μm.
Further, the grating period d can also be above 5 μm. However, it is
preferably always so chosen that at least two facets 6 are present per
pixel 5. In particular, at least three, four, or more facets 6 can be
contained per pixel 5.

[0101] The facets 6 are preferably configured as planar area elements. It
is also possible, however, that the facets 6 are curved (e.g. concave or
convex). The facets 6 can extend straight, as shown for the facets 6 of
the pixels 51-55 in FIG. 2. However, a non-straight course
(e.g. slightly curved) is also possible, as schematically shown for the
pixel 56 in FIG. 2.

[0102] Furthermore, a color-shift thin-film system 18 or a thin-film
system 18 can be vapor-deposited on the upper side 8 or on the reflective
coating 12 on the upper side 8, as indicated in FIG. 6. The reflective
coating 12 can be configured as a metal film on which there are provided
a dielectric layer 13 as well as an upper metal layer 14 which is partly
transparent. It is of course also possible to form on the metal film 12 a
dielectric thin-film system comprising first, second and third layers 15,
16, 17, whereby the first and third layers 15, 17 have a higher
refractive index than the second layer 16 (FIG. 7).

[0103] With such a construction it is possible to replace known security
inks in which platelet-shaped pigments with a thin-film interference
coating change their color depending on the viewing angle. A comparable
optical effect is obtained, whereby the optically perceptible quality is
considerably better in comparison to security inks. Considerably more
brilliant colors can be produced with the security element of the
invention.

[0104] In FIG. 8b there is shown a development of the security element 1
of the invention. The orientation of the facets 6 is so chosen here that
they respectively have only a relatively small angle of inclination in
the region of the middle stripe represented in white. For example, angles
of inclination can be chosen from the range of ±5°. The further
away the facets 6 are from the middle, the greater the average angle of
inclination becomes, whereby the angles of inclination continuously
increase in the upward direction in FIG. 8b and continuously decrease in
the downward direction in FIG. 8b. In other words, the limits of the
range from which the angles of inclination can be chosen shift toward
greater angles of inclination with increasing distance from the middle.
The azimuth angles are respectively chosen here from such a range that
the average angle of reflection is upward in the upper region and
downward in the lower region.

[0105] Looking perpendicularly, upon perpendicular illumination, at the
security element 1 shown in FIG. 8b, the digits of the number 50 appear
brighter in the region of the middle stripe 20 than in the other regions,
which is indicated by the white representation. The described glittering
effect of course also still occurs, because the pixels still have
different reflection directions (here within the described limits).

[0106] Now tilting the security element 1, the stripe 20 apparently rolls
upward or downward during the tilting. In FIG. 8a there is shown a tilted
position in which the lower region of the security element 1 is tilted
into the sheet plane and thus the upper part of the security element 1
tilted out of the sheet plane. In this case, the stripe 20 has apparently
traveled upward. In FIG. 8c there is shown the opposite tilt, at which
the upper part is tilted into the sheet plane and the lower part of the
security element tilted out of the sheet plane. In this case, the stripe
20 has apparently traveled downward. Such an effect is also designated
"rolling bar".

[0107] In particular when the security element 1 is configured as a
security thread 19 (FIG. 1) it is expedient to use arrangements in which
there are not only individual stripes 20 traveling upon tilting, but the
effect is periodically continued. Thus, for example for a security thread
19 emerging on the surface of the bank note 2 in certain window regions,
a multiplicity of such effects can be repeated periodically at an e.g. 5
mm repeat. In a window region with e.g. a 10 mm height, the effect can
hence always be perceived at least twice, i.e. there are always at least
two bright stripes 20 to be seen.

[0108] It is of course also possible to predefine the average orientation
of the facets of the individual pixels such that upon a tilting of the
security element 1 a bar extending perpendicularly to the tilting axis
moves along the tilting axis. This case is indicated in FIGS. 9a to 9c.
In FIG. 9b the appearance of the security element 1 is represented upon
perpendicular viewing and illumination. There is a middle stripe 20
present which, in this tilted position, appears brighter than the
remaining regions of the first areal region 3 and which extends
vertically here.

[0109] When the security element 1 is now tilted (FIG. 9a shows the tilt
at which the lower side is tilted into the sheet plane, and FIG. 9c shows
the tilt at which the lower side is tilted out of the sheet plane), the
vertical bar 20 apparently travels from the left to the right.

[0110] The average inclination in the region of the stripe 20 is
relatively low at the position of FIG. 9b and respectively increases
continuously to the right and left. The azimuth angles are so chosen here
that the facets are aligned upward in the left region for example, and
downward in the right region for example. Thus, the described effect can
be obtained, whereby here, too, the glittering impression is again
obtained due to the random variation of the orientation of the facets of
different pixels, even if only a certain narrow variation range is
predefined per region.

[0111] According to an embodiment not shown here, the security element 1
can be arranged on a bank note 2 which further contains a security
feature that is based on preferably platelet-shaped magnetic pigments
which are aligned relative to the surface of the bank note such that they
show a so-called "rolling bar" effect. Such alignments can be taken in
particular from U.S. Pat. No. 7,517,578 B2. The security element 1 and
the magnetic security feature are arranged here relative to each other
such that the bright stripe of the security element 1 and the bright
stripe of the magnetic security feature travel in mutually perpendicular
directions upon tilting of the bank note 2.

[0112] Besides the described, moving stripe upon tilting of the security
element, there can of course also be realized other known kinetic effects
upon tilting of the security element 1, such as e.g. so-called flip,
running or pumping effects.

[0113] Some of the above-described effects are impossible, or at least
very difficult, to realize with conventionally known pigment inks.

[0114] The security element of the invention can be manufactured by first
dividing the first areal region 3 computationally into the pixels 5. Then
a desired orientation is predefined computationally for each pixel 5.
Said orientation can correspond e.g. to the average expected orientation
of a pigment of known security inks. In particular, a grating period or
the width of the sawteeth d can be predefined. The substantially random
variation of the orientations of the facets 6 is then preferably so
realized that, starting out from such a preferential orientation, the
orientation of the facets 6 of the individual pixels 5 is then varied for
example on the basis of computer-generated random numbers or
pseudo-random numbers. It can thus be achieved in particular that the
orientations of the facets 6 of individual pixels 5 fluctuate around a
predefined average orientation. The random variations of the orientation
can be effected in one or two dimensions or spatial directions. Thus, the
variation can in particular also relate only to the slope a or only to
the azimuth angle Φ, or the variation of the orientations of the
facets 6 can be chosen such that a reflected light beam incident in a
corresponding partial region fans out around a predefined rotation
direction. On the basis of these data the sawtooth structures of the
individual pixels 5 can then be produced for example by means of gray
scale lithography. This structure can then be electroformed and embossed
on foil in UV lacquer 9 by mass production. Subsequently, the metal film
12 is vapor-deposited and then optionally the thin-film interference
coating 18.

[0115] In the security element 1 of the invention, the orientations of the
facets 6 of the pixels 5 can be produced with high exactness, so that a
very fine resolution can be obtained on the small length scale of the
pixels 5. In particular, arbitrarily sharp or gentle transitions can be
produced by the individual pixels 5. The orientation can be defined in
the described way for each facet 6, and the security element 1 can then
be manufactured according to this definition.

[0116] The security element 1 of the invention can also be configured as a
security thread 19 (FIG. 1). Further, the security element 1 can not
only, as described, be formed on a carrier foil from which it can be
transferred to the value document in the known way. It is also possible
to form the security element 1 directly on the value document. It is thus
possible to carry out a direct printing with subsequent embossing of the
security element onto a polymer substrate, in order to form a security
element according to the invention on plastic bank notes for example. The
security element of the invention can be formed in many different
substrates. In particular, it can be formed in or on a paper substrate, a
paper with synthetic fibers, i.e. paper with a content x of polymeric
material in the range of 0<x<100 wt %, a plastic foil, e.g. a foil
of polyethylene (PE), polyethylene terephthalate (PET), polybutylene
terephthalate (PBT), polyethylene naphthalate (PEN), polypropylene (PP)
or polyamide (PA), or a multilayer composite, in particular a composite
of several different foils (compound composite) or a paper-foil composite
(foil/paper/foil or paper/foil/paper), whereby the security element can
be provided in or on or between each of the layers of such a multilayer
composite.

[0117] In FIG. 10 there is shown in plan view a further embodiment of the
security element 1 of the invention wherein the first areal region 3 is
again formed by the digits of the number 50 and the second areal region 4
is adjacent to the first areal region 3 such that the two areal regions 3
and 4 together fill the total area that is limited by the rectangular
outside contour of the optically variable area pattern 1. The first
region 3 can be configured in the ways described in connection with FIGS.
1 to 9, so that for example the glittering effect of the invention and/or
the described noisy representation can be achieved. In particular the
"rolling bar effect" described in connection with FIGS. 8a-8c can be
provided.

[0118] The second areal region 4 is configured here as a moire
magnification arrangement, which will hereinafter be described in detail,
which represents the letter "M" for the viewer with absolute depth
information. This results for the viewer in a total representation in
which the two areal regions 3, 4 or the individual representations
presented by the areal regions 3 and 4 yield a total image, whereby the
two areal regions 3, 4 preferably adjoin each other directly.

[0119] Advantageously, the two areal regions can be combined on the same
carrier 9 (which can be configured e.g. as a foil strip) and in
particular be embossed by the same operations.

[0120] In FIG. 11 there is represented a schematic sectional view of the
security element 1 according to FIG. 10, whereby the sectional view shows
a portion of the first areal region 3 which is adjoined on both sides by
the second areal region 4. The sectional view according to FIG. 11 is
purely schematic and not true to scale and serves essentially to explain
the construction.

[0121] As indicated by the sectional view according to FIG. 11, the
carrier 9 has a carrier foil 21 (which can be for example a PET foil) as
well as upper and lower embossing lacquer layers 22, 23.

[0122] In the region of the first areal region 3, facets 6 of the pixels
52 and 53 are represented schematically. By means of the facets
6 the desired reflection of the individual pixels 52, 53 is
obtained.

[0123] To present the letter "M" with the desired absolute depth
information in the second areal region 4, there are formed in the lower
embossing lacquer layer 23 microstructures 24 which can in particular be
filled with ink. The microstructures 24 are arranged in a plane
perpendicular to the drawing plane of FIG. 11 in a grid with fixed
geometry (here for example a hexagonal grid) and thus areally in a first
microstructure pattern.

[0124] The upper embossing lacquer layer 22 is so configured that it has a
multiplicity of microlenses 25 in the second areal region 4. The
microlenses 25 are arranged in a plane perpendicular to the drawing plane
of FIG. 11 in a grid with fixed geometry (here for example a hexagonal
grid) and thus areally in a first pattern, whereby the first pattern is
so adjusted to the first microstructure pattern and the two patterns are
so aligned with each other that upon viewing of the security element 1
the microlenses 25 form together with the microstructures 24 a moire
magnification arrangement. The basic principle of a moire magnification
arrangement is described for example in WO 2006/087138 A1, whose total
content is hereby incorporated.

[0125] The moire magnification arrangement in the second areal portion 4
forms a micro-optic representation arrangement 26, with which, as to be
described in detail hereinafter, the letter "M" is so represented to the
viewer in multiple fashion here that it appears behind the security
element 1. This is obtained by the viewer's left and right eyes LA and RA
being presented different views of the object to be represented (here the
letter "M") which respectively show the object viewed from the
corresponding direction. In FIG. 12, for simplifying the representation,
the object is drawn in as a point, whereby the viewer's right eye RA sees
the object at the position 27 and the viewer's left eye LA sees the
object at the position 28. Thus, the viewer sees the object with his two
eyes from the different directions 29, 30 which intersect at the position
31, so that for the viewer the object is located at the position 31 and
hence at distance t1 behind the security element 1. For the viewer there
thus results absolute depth information for the object.

[0126] With the second areal region 4 there is thus obtained e.g. at a
constant viewing angle a representation independent of the illumination
direction, while in the first areal region 3 there occurs e.g. the
glittering effect at a varying illumination direction.

[0127] Through the moire magnification arrangement in the second areal
region 4 there is obtained an absolute depth effect by which the
periodically recurring letter "M" located at the depth t1 is represented
to the viewer. The microstructures 24 can, as mentioned above, preferably
be filled with ink, so that the letters "M", on the one hand, and the
remaining region of the second areal region 4, on the other hand, appear
matt but of different color.

[0128] The micro-optic representation arrangement 26 can be configured not
only as a moire magnification arrangement, but for example also as a
modulo magnification arrangement, as described e.g. in WO 2009/000528 A1.
The content with regard to the formation of a modulo magnification
arrangement of WO 2009/000528 A1 is hereby incorporated into the present
application. With a modulo magnification arrangement the image to be
represented need not necessarily be composed of a grating of periodically
repeating single motifs, in contrast to a moire magnification
arrangement. A complex single image with high resolution can be
represented. In the moire magnification arrangement, the image to be
represented normally consists of single motifs (here microstructures 24)
which are arranged periodically in a grating and which are represented in
magnified form by the lenses 25, whereby the area associated with each
single motif maximally corresponds approximately to the area of the
corresponding lens cell.

[0129] In the described embodiment, the microlenses 25 as well as the
sawtooth structures for the reflective facets 6 can be produced
simultaneously side by side by means of only a single embossing of the
embossed layer 22. Subsequently, the facets 6 only need to be metallized
in order that they act reflectively. The construction according to FIG.
11 is hence quick to manufacture.

[0130] In FIG. 13 there is shown a modification of the security element 1
of the invention wherein the micro-optic representation arrangement 26
has, instead of the microlenses 25, concave mirrors 32 which are formed
by embossing of the lower embossing lacquer layer 23 and application of a
mirroring coating.

[0131] The facets 6 of the pixels 52, 53 are also formed on the
lower embossing lacquer layer 23. They can be formed in the same way as
the concave micromirrors 32 by embossing and mirror-coating. Preferably,
the concave micromirrors 32 and the facets are embossed in the same step
and mirror-coated in the same step.

[0132] The microstructures 24 can be provided not only in the second areal
region 4, but also in the first areal region 3 and thus above the facets
6. This facilitates the manufacture of the security element 1. However,
they can also be omitted.

[0133] If the microstructures 24 are provided in the first areal region 3
and filled with an ink, the first areal region 3 can (but does not have
to) likewise appear slightly colored.

[0134] In FIG. 14 there is shown a construction of the security element 1
wherein the concave micromirrors 32, the microstructures 24 and the
facets 6 are respectively embossed separately in their own embossing
lacquer layers 23, 22 and 33. Between the embossing lacquer layers 23 and
22 there is provided a first carrier foil 21 and between the embossing
lacquer layers 22 and 33 a second carrier foil 34.

[0135] This construction requires more working steps for manufacture in
comparison to the variants according to FIGS. 11 and 13, but offers the
advantage that the origination of the concave micromirrors 32 and of the
facets 6 can be effected separately from each other. The original of the
concave micromirrors 32 can even be the same in different designs,
because there is always only required a homogeneous area covered with
concave micromirrors 32. Once an original with very good imaging
properties has been manufactured, it can be utilized for manufacturing
many different security elements 1. Further, the concave micromirrors 32
and the facets 6 can be metallized differently, for example with
different metals or coatings with color-shifting effects (e.g. thin-film
systems in which the color varies in dependence on the viewing angle).

[0136] In the variants according to FIGS. 13 and 14 with the concave
micromirrors 32, a further protective lacquer layer (not shown) can
further advantageously be provided on the upper side or underside of the
security element 1, so that the resistance as well as the protection from
molding by forgers can be increased.

[0137] In particular upon the viewing of the security element 1 in
transmitted light against a bright light source, the micro-optic
representation arrangement 26 can also have, instead of a microfocusing
element grid (grid of the microlenses 25 or grid of the concave
micromirrors 32), only a hole grid 35, as shown in FIG. 15. Such a hole
grid 35 can be realized for example by periodically arranged holes or
slots in an opaque, for example reflectively metallized, layer. The holes
here can be small gaps. In this case, the holes can be designated
positive holes. There can also be provided so-called negative holes,
which holes are small, non-transparent or non-mirroring regions.

[0138] In the embodiment shown in FIG. 15, the hole grid also extends into
the first areal region 3, so that a superimposition of the
representations results in the first areal region 3. The security element
1 can of course also be configured such that no hole grid is present in
the first areal region 3.

[0139] Further, in the security element 1 of the invention, the
micro-optic representation arrangement 26 can be realized by means of
diffractive structures. Thus, there can be provided for example a
hologram with a stereographic 3D representation which is constructed from
microscopically small sine gratings.

[0140] Alternatively, the object represented by means of the micro-optic
representation arrangement 26 can also apparently lie or float in front
of the security element 1.

[0141] The micro-optic representation arrangement 26 and/or the facets 6
can be provided wholly or partly with a color-shifting coating, in
particular a thin-film with reflector/dielectric/absorber. This makes it
possible to further enhance the optical attractiveness and further
increase the forgery resistance.

[0142] In the embodiment examples hitherto described, the micro-optic
representation arrangement 26 in the second areal region 4 was
respectively configured so as to obtain a stereographic representation
with depth information. This is understood here to mean representations
in which a three-dimensional effect is generated by the security element
1 providing the viewer's left and right eyes with different views of an
object which respectively show the object viewed from the corresponding
direction. From these different views there then results absolute depth
information for a viewer, resulting altogether in a three-dimensional
impression. The employed representations in this class can often have
more than only two different views, which usually also results in a
parallax (i.e. upon rotation the image components in the foreground move
relative to the image components in the image background). In some cases
one can for example, by rotation, also look behind an object that is in
the foreground.

[0143] This can be realized technically by three-dimensional holograms,
for example directly exposed holograms or computer-generated stereograms.
Further examples are microlens tilt images and moire magnification
arrangements with a depth effect or kinetic effect, as described e.g. in
WO 2007/076952 A2 or WO 2009/000527 A1.

[0144] In a further embodiment, the micro-optic representation arrangement
26 can now be configured such that the parallax does not correspond
exactly to the parallax of an object located in depth. This can be
realized for example by moire magnification arrangements or modulo
magnification arrangements. It can thereby be achieved that upon tilting
or rotation of the security element 1 an additional kinetic effect occurs
in the second areal region 4. This may be an orthoparallactic motion, as
described e.g. in WO 2007/076952 A2, whereby the representations for the
viewer's left and right eyes permit no assignment of a depth, strictly
speaking, because the viewing directions from which the observer sees the
object with his left and right eyes do not intersect. In a preferred
variant, only a relatively small error of the parallax is present, so
that the viewing directions (29 and 30 in FIG. 12) almost intersect and
the viewer sees an object that moves upon tilting or rotation of the
security element 1, but which he, despite the parallax error, ranges
clearly e.g. at a depth located behind the plane of the security element
1.

[0145] In the A matrix formalism of the application WO 2009/000528 A1, a
representation with correct parallax corresponds to a representation with
an A matrix which is only populated on the diagonal. In an
orthoparallactic representation the A matrix is only populated at the
places not located on the diagonal. A small parallax error is present
when the A matrix is populated on the diagonal as well as therebeside.

[0146] In a further embodiment of the security element 1, the
representation by means of the micro-optic representation arrangement 26
can change from a first image to a second image upon tilting or rotation
of the security element 1. Thus, for example an image, located in depth,
of a first symbol A could tilt into at least one other representation,
for example a symbol B, upon tilting of the security element 1.

[0147] The micro-optic representation arrangement 26 can also realize
additional effects besides a three-dimensional effect, for example tilt
images or kinematic effects (motions, pumping effect, etc.). In the
above-mentioned modulo magnification arrangements, the three-dimensional
representation in the second areal region 4 can move upon tilting of the
security element 1. Alternatively, as of a certain tilting angle the
representation could also tilt into the representation of a completely
different object not necessarily likewise appearing three-dimensionally
(for example a number located in depth can change to another
representation, for example a symbol then moving upon further tilting).

[0148] It is especially advantageous in the embodiments where the
micro-optic representation arrangement 26 and the facets 6 are embossed
into the same embossing lacquer layer 22 (FIGS. 11 and 14) that a
micro-optic representation arrangement 26 can be upgraded to the security
element 1 of the invention with extremely little effort. It is merely
necessary to write the facets 6 additionally between or beside the
microlenses 25 or concave micromirrors 32 upon origination.

[0149] The security element 1 of the invention can also be designated an
optically variable area pattern and used e.g. for purely decorative
purposes.

[0150] In FIG. 16 there is shown schematically an embossing tool 36 with
which the facets 6 as well as the microlenses 25 can be embossed in the
upper embossing lacquer layer 22 of the security element 1 according to
FIG. 11. For this purpose, the embossing tool 36 has an embossing area 37
in which the inverted form of the surface structure to be embossed is
formed.

[0151] A corresponding embossing tool can of course not only be provided
for the embodiment according to FIG. 11. An embossing tool can also be
made available in the same manner for the other described embodiments.